rewrite.pl

#!/usr/bin/perl

$mirror = "nz.archive.ubuntu.com";
#$mirror = "us.archive.ubuntu.com";
# For Cape Town
#$mirror = "ubuntu.saix.net/ubuntu-archive";

$| = 1;
while (<>) {
    @line = split;
    $_ = $line[0];
    if (m/^http:\/\/((?:[a-z0-9]+\.)?archive\.ubuntu\.com)\/(.*)/ &&
        $1 ne $mirror) {
        print "http://" . $mirror . "/" . $2 . "\n";
    } else {
        print $_ . "\n";
    }
}